1. Field of the Invention
The present invention relates to an optical transmission apparatus, an optical repeater and an optical cross-connect equipment, and in particular, relates to an optical transmission apparatus, an optical repeater and an optical cross-connect equipment, each having an optical amplifier by means of an optical fiber doped with Erbium, etc., therein.
2. Description of Related Art
In a network constructed by connecting a plurality of node equipment, normally, there is used an optical transmission apparatus in the node equipment thereof, each having an optical amplifier which is formed with optical fiber doped with Erbium, etc. (hereinafter, it is called xe2x80x9cdoped fiberxe2x80x9d) and a pumping light source therein. Such the optical transmission apparatus, receiving a data optical signal and a supervisory optical signal, which are different in wavelength thereof to each other and are supplied from an upper stream side, amplifies the data optical signal for outputting it to a downstream side thereof. Alternatively, the optical transmission apparatus, taking it into the node equipment of itself, also has a function of receiving the supervisory optical signal and outputting a new supervisory optical signal to a downstream side thereof, or of outputting the data optical signal, on which data from inside of the node equipment of itself is carried, to the downstream side. The optical transmission apparatus in accordance with the related prior art, for achieving the functions mentioned in the above, is so constructed that it comprises two light sources, i.e., a pumping light source for pumping the doped fiber and a light source for the supervisory optical signal.
The optical transmission apparatus in accordance with the related prior art must have at least two kinds of light sources, therefore, it has drawback that components of the total optical transmission apparatus become very large in the number as well as becoming complex in the construction thereof.
An object is, in accordance with the present invention, for dissolving the drawbacks in the conventional related arts mentioned in the above, to provide an optical transmission apparatus, an optical repeater, an optical cross-connect equipment, a node equipment, and an optical network, which can be simplified in construction to be cheaply constructed.
In accordance with the present invention, the above-mentioned object is accomplished by an optical transmitting apparatus, comprising: one or more of doped fibers for amplifying an input data optical signal by a pumping light; and an optical wavelength multiplexer for outputting a supervisory optical signal, which is different from the data optical signal in the wavelength thereof, being multiplexed with the data optical signal outputted from the one or more of doped fibers, wherein a common light source is provided, i.e., for the pumping light source, as well as for the optical source of the supervisory optical signal.
Further, the object mentioned above is also achieved by the optical transmission apparatus, which further comprises an optical coupler for distributing the output light emitted from the common light source for the pumping and the supervisory optical signal as mentioned in the above, to the one or more of doped fibers and to the optical wavelength multiplexer, wherein the common light source is so controlled that it outputs a light modulated by a supervisory information, alternatively, which further comprises a modulator for modulating a light depending on the supervisory information, positioned between the optical coupler and the optical wavelength multiplexer, wherein the common light source for the pumping and the supervisory optical signal is so controlled that it outputs a light at a constant output by a direct current signal.
Further, the object mentioned in the above is also achieved by the optical transmission apparatus, which further comprises an optical wavelength multiplexer for dividing the inputted optical signal into the supervisory optical signal and the data optical signal, and a reveiver of the supervisry optical signal.
In accordance with the present invention, the object mentioned in the above is achieved an optical cross-connect equipment having optical switches, each having a plurality of input terminals and output terminals, and a controller for controlling the optical switches, further comprising the above-mentioned optical transmission apparatus being connected to the plurality of input terminals of the optical switches and to the plurality of output terminals thereof, respectively, or alternatively, further comprising a plurality of data signal transmitters and a plurality of data signal receivers, which are connected to the input terminals of the optical switches, thereby controlling the optical switch, the data signal transmitter, the data signal receiver and the plurality of optical transmission apparatuses by the controller, or, by providing the common light source for pumping of the doped fiber and for supervisory optical signal which are necessary for the optical transmission apparatus, in common with the plurality of optical transmission apparatuses.
Further, the above-mentioned object is also achieved by an optical cross-connect switch, comprising: an optical circuit, which includes a plurality of input and output terminals for the optical signals; and a controller for controlling the optical circuit, wherein the optical circuit includes a wavelength multiplexer, a wavelength divider, an optical amplifier, or a regenerator other than the optical switches.
Further, the above-mentioned object is achieved by an optical network constructed by connecting a plurality of node equipment through optical fibers therebetween, wherein each of the plurality of node equipment is constructed with the optical cross-connect equipment mentioned in the above, or alternatively, by providing an optical repeater which includes the above-mentioned optical transmission apparatus on the way of transmission path or line with the optical fibers connecting between those node equipment.